Thanks. I thought nobody was gonna answer my question. I'm talking about uv texture coordinates. As you can see from the file, cube.fbx, there are 8 vertices and 12 uvs, I should have 8 vertices and 8 uvs in order to load in direct3d. As fellow gamedev people told me, what I should do is duplicate vertices. I have no idea how to do that easily.
Geometry: 964450576, "Geometry::", "Mesh" {
Vertices: *24 {
a: -0.5,-0.5,0.500000059604645,0.5,-0.5,0.500000059604645,-0.5,0.5,0.500000059604645,0.5,0.5,0.500000059604645,-0.5,0.5,-0.499999940395355,0.5,0.5,-0.499999940395355,-0.5,-0.5,-0.499999940395355,0.5,-0.5,-0.499999940395355
}
PolygonVertexIndex: *30 {
a: 0,1,-3,2,1,-4,2,3,-5,4,3,-6,4,5,-7,6,5,-8,1,7,-4,3,7,-6,6,0,-5,4,0,-3
}
Edges: *17 {
a: 0,1,2,4,5,7,8,10,11,13,14,16,17,18,19,24,25
}
GeometryVersion: 124
LayerElementNormal: 0 {
Version: 101
Name: ""
MappingInformationType: "ByPolygonVertex"
ReferenceInformationType: "Direct"
Normals: *90 {
a: 0,0,1,0,0,1,0,0,1,0,0,1,0,0,1,0,0,1,0,1,0,0,1,0,0,1,0,0,1,0,0,1,0,0,1,0,0,0,-1,0,0,-1,0,0,-1,0,0,-1,0,0,-1,0,0,-1,1,0,0,1,0,0,1,0,0,1,0,0,1,0,0,1,0,0,-1,0,0,-1,0,0,-1,0,0,-1,0,0,-1,0,0,-1,0,0
}
}
LayerElementUV: 0 {
Version: 101
Name: "map1"
MappingInformationType: "ByPolygonVertex"
ReferenceInformationType: "IndexToDirect"
UV: *24 {
a: 0.331844329833984,0.000959634780883789,0.665735721588135,0.000959277153015137,0.665736198425293,0.334850549697876,0.331844806671143,0.334850788116455,-0.00204682350158691,0.000959992408752441,0.999627113342285,0.334850549697876,0.665736436843872,0.668741941452026,0.331845045089722,0.668741941452026,0.999627113342285,0.000959277153015137,-0.00204646587371826,0.334851264953613,0.665736198425293,1.00263357162476,0.331844806671143,1.00263357162476
}
UVIndex: *30 {
a: 0,1,3,3,1,2,3,2,7,7,2,6,7,6,11,11,6,10,1,8,2,2,8,5,4,0,9,9,0,3
}